Studies done during the course of this project include: (1) identification of dominant transforming genes present in human tumor cell lines and in naturally occurring human tumors; (2) molecular cloning of an oncogene present in T24 bladder carcinoma cells; (3) physical mapping of the T24 oncogene and characterization of the transforming region; (4) isolation of a normal gene homologous to the T24 oncogene from a library of human fetal liver DNA; (5) biochemical comparison of the normal and transforming alleles; (6) identification of the transcriptional and translational products of the T24 oncogene; (7) relationship of the T24 oncogene with other transforming genes including those present in acute transforming retroviruses.